Design Of Beidou Navigation Antenna

The satellite navigation and positioning system plays a very important role in people's production and life.As the transmitting and receiving channel of electromagnetic wave,the antenna is very important to the navigation system.In this paper,the satellite navigation technology is briefly introduced,and then the development of the BDS in our country and the design requirements are emphatically introduced.At the same time,the basic theory of navigation antenna is introduced,and three different types of multiband circularly polarized Beidou navigation antenna are designed based on the above theory.Firstly,This paper introduces the basic knowledge of microstrip antenna and analysis method,and based on the theoretical basis of a multiband microstrip antenna design,the antenna by using a multilayer stack is realized in B3,L and S three bands,and meet the design requirements in the VSWR,AR and Gain.Measured results meet well with the simulated results.On the basis of this antenna,combining with the crossed dipole antenna,and the new antenna is realized by 3d B bridge in B1,B3,L and S four bands.Secondly,based on the quadrifilar helix antenna theory study,the influence of quadrifilar helix parameters on antenna radiation performance,a basic four arm spiral antenna is designed.Based on the antenna,design a type of the printed quadrifilar helix antenna working in B1 and B3 two bands,the sub strate with a thickness of 2mil,the dielectric constant is 3.48 poly ester imide,the AR,Gain and VSWR meet the requirements,and has the advantages of simple processing,easy popularization.Finally,in order to achieve the broadband antenna,we design a spiral slot antenna which the material of the dielectric constant is the FR4.The material is a hollow cylindrical body,thereby reducing the size.The connected with the power divider network,its overall size is??545858mmmmmm.The working frequency is between 1.127 GHz to 1.656 GHz,including the center frequency of B1 B2 and B3 three bands.Within the working frequency,the axial Gain is greater than 0.8d B,the low elevation Gain is more than-3.5d B,the VSWR is less than 1.5,and the AR is less than 1.8d B.